Die spotting press



7 Sheets-Sheet .2

J. M. ATOLS DIE SPOTTING PRESS Jan. 16, 1962 Filed March 8, 1960 INVENTOR. Jblzn I72, dials BY ,MW 0% 50M after/1691a Jan. 16, 1962 J. M. ATOLS 3,016,770

DIE SPOTTING PRESS Filed March 8, 1960 7 Sheets-Sheet 3 INVENTOR. 1.15/77? 97?,

MWJNQ YQM Qitornegs Jan. 16, 1962 J. M. ATOLS DIE SPOTTING PRESS 7 Sheets-Sheet 4 INVENTOR. Jbhn Vilfliols Filed March 8, 1960 4 90k 09M 5 7 W zlifornays Jan. 16, 1962 J. M. ATOLS 3,01

DIE SPOTTING PRESS Filed March 8, 1960 '7 Sheets-Sheet 5 INV EV TOR.

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DIE SPOTTING PRESS Filed March 8, 1960 7 Sheets-Sheet 6 124\ INVEN TOR.

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DIE SPOTTING PRESS Filed March 8, 1960 7 Sheets-Sheet 7 Fire. 16

INVENTOR. JOMWM & M,W, film WQW Bfilhfllh Patented Jan. 16, 1962 ice 3,tl16,77ll Bid SiDT'HNG PRESS John M. Atols, t'jhicago, iii, assignor to Atols Tool and Mold Corporation, Chicago, iii, a corporation of Illinois Filed Mar. S, 196%, Ser. No. 13,609 11. Claims. (ill. 76--4) This invention relates to apparatus for inspecting and finishing dies, and more particularly to apparatus known as a die spotting press.

The manufacture of dies for stamping sheet metal articles, for example the large and heavy dies like those used for forming parts of automobile bodies or the like, involves a finishing process of fitting two die parts together. This requires a considerable amount of inspection and filing and grinding to make the die parts fit together properly. In addition, repeated trial engagements of the die parts are necessary to determine where high spots exist which must be removed.

It has been customary for this finishing process to use a special machine or die spotting press to move the die parts together so that production die presses need not be used and thus kept out of service. Besides, the die presses used in production are not well adapted for die spotting because they usually do not have a large enough stroke to permit a workman to get between the die parts to perform the necessary inspection and filing and grinding operations. In addition, it is undesirable from the safety standpoint to permit a workman to get under or between the large and heavy die parts.

Prior die spotting presses have a number of disadvantages. In particular, the die parts when separated generally were held in the spotting press in horizontal position. Some dies are very large, and with such dies in horizontal position the workman often was unable to reach all pmts of the die from one side of the machine, making it necessary to walk around the machine and work from other sides. In addition, where the dies were extremely large, the workman usually had to climb on the die parts in order to inspect them and to perform the required machining operations.

This was awkward, and because of the repeated trial engagements necessary in the die spotting process it was time consuming and laborious. Consequently, the prior die spotting operations on the larger dies often required the cooperative efforts of several workmen. This increased the cost of the entire operation.

It is apparent that it would be desirable to provide a die spotting press in which the die parts can be separated and moved to a position such that regardless of their size, there is no necessity for more than one workman or for the workman to climb on or between the die parts for inspection and machining purposes.

In addition it would be desirable for such a die spotting press to be provided with automatic safeguards to prevent the die parts from moving together unless they are properly aligned and to control the pressure used in bringing the die parts into engagement.

What is needed therefore, and comprises an important object of this invention is to provide a die spotting press which has the above described advantageous features.

In the present die spotting press, the die parts are held for the inspection and machining operations in an inclined position, the die surfaces sloping upwardly from the front E the rear of the press and at convenient height above the cor.

This and other objects of the invention will become more apparent when read in the light of the accompanying specification wherein:

FIG. 1 is a front perspective view of a die spotting press embodying the invention, with die pants mounted thereon and shown in a mating position;

FIG. 2 is a fragmentary front perspective view of the spotting press showing the dies in a separated position and facing each other;

FIG. 3 is a fragmentary front perspective view of the spot-ting press with the dies held in the inclined inspection and grinding position;

FIG. 4 is a sectional view taken on the line 44 of FIG. 2;

FIG. 5 is a fragmentary elevational view taken on the line 5-5 of FIG. 4;

FIG. 6 is a fragmentary elevational view taken on the line 6-6 of FIG. 4;

FIG. 7 is a sectional view taken on the line 7-7 of FIG. 4;

FIG. 8 is a sectional view taken on the line 88 of FIG. 2;

FIG. 9 is a perspective view of the cam latch member;

FIG. 10 is a perspective view of the latch member;

FIG. 11 is a fragmentary elevational View taken on the line 11-11 of FIG. 8;

FIG. 12 is a sectional view like that of FIG. 4, but with the platen swung into inspection position;

FIG. 13 is a sectional view taken on the line 13-13 of FIG. 12;

FIG. 14 is a side elevational view of a portion of the platen showing the profile of a keeper member;

FIG. 15 is an end view of the platen;

FIG. 16 is an elevational view of a portion of the platen and supporting bracket, showing the locking engagement between the latch member and the keeper;

FIG. 17 is a side elevational view of one of the piston rods used to pivot a platen, and

FIG. 18 is a plan View, partially in section, of a part of the rear of the spotting press.

Referring now to FIG. 1 of the drawings, the present die spotting press It includes a frame indicated generally by the reference numeral 12. The left hand end, looking at the front of the press, is designated 13. The frame includes vertically disposed end plates 14 and 16 which are connected together by horizontal connecting and guide bars as described below. End plates 14 and 16, as shown, are generally triangular in shape (FIG. 4), although the shape is not critical.

End plates 14 and 16 have downwardly extending legs 13 and 20, and legs 18, as illustrated, are about twice as long as legs 20 so that the base of each of the triangular end plates is inclined to the horizontal. Nuts 21 are secured to the corners of each of the end plates and to a lug 23 projecting downwardly from the base of each end plate (FIG. 4).

As stated above, the end plates are connected together in spaced parallel relationship by means of four connecting and guide bars 22, 24', 26 and 28. The guide bars all have threaded ends, and the ends of guide bars 22, 24 and 26 are in threaded engagement with nuts 21 mounted on the corners of end plates 14 and 16. The ends of guide bar 28 are in threaded engagement with the nuts 21 secured to depending lug 23. With this arrangement, the

entire frame 12 stands on the legs 18 and 20 of the two end plates.

A generally triangular carriage plate 3!} is provided,

3 plate 3%. A roller wheel 38 is mounted on these angle members, and is in rotatable engagement with guide bar 28. As will be described below, heavy equipment, including a massive die part, is mounted on carriage plate 313. Thus, guide bar 223 and roller wheel 38 cooperate to carry part of the Weight so carriage plate 31 will slide easily on guide bars 22, 24 and 2s.

To prevent guide bar 28 from deflecting under load, a plurality of legs ill may be provided, see FIGS. 1 and 11. These are important because excessive deflection in bar 28 would cause the substantial Weight of carriage plate 36 and associated mechanism to be carried by guide bars 22, 24 and 26, thereby making it difficult to shift the carriage plate 34) on these guide bars.

A mechanism, see FIG. 18, is provided to move carriage plate 3! back and forth on guide bars 22, 2d and 26. In the embodiment shown, this mechanism includes a hydraulic cylinder 42 and cooperating piston (not shown) which are part of the control system of press 10. Cylinder 42 is adjustably mounted in end frame 16, see FIGS. 1 and 18. A piston rod 4-4 is secured at one end to the piston, and its opposite end is secured to carriage plate 3% The cylinder is provided with electrically operated valves (not shown) on each side of the piston to provide desired movement of the piston, piston rod 44 and carriage plate Fall.

A threaded rod 48 (FIG. 18) is secured to the closed or rear end of cylinder 42. This rod is in threaded engagement With a nut 55) which is rotatably mounted in bearing 52 of end plate 16. A control wheel 54 is secured to nut 5%. Rod 48 is provided with a longitudinally extending slot 56, and a key 58 secured to end plate 16 rides in this slot. This arrangement prevents rod 48 from rotating when control wheel 54 and nut 50 are rotated. Consequently, rotation of control wheel 54! causes rod 48 to move longitudinally. With this structure, the position of cylinder 52 is longitudinally adjustable for reasons to be described below. To prevent dust or other foreign matter from affecting rod 43, shields s and 62 may be provided as shown in FIG. 1.

Referring again to FIG. 1, upper edge 64 of end plate 14 and upper edge 65 of end plate 1e are inclined at an angle of about 45 degrees to the horizontal.

Two'bracket members 68 and 70 are mounted on end plate 1d (FIG. 2). The bracket members are shown generally L-shaped with bracket member 68 having a flange 72 and a support plate 74, while bracket member '70 has a flange '76 and a support plate 78. Flanges 72 and 76 are secured to inner surface 86 of end plate 14, and the support plates are positioned so they extend longitudinally of the press in a generally perpendicular direction from inclined upper edge 64 of end plate 14.

Support plates '74 and 78 are provided with aligned openings in which a pivot rod 82 is mounted. With this arrangement, pivot rod $2 is parallel to end plate 14 and inclined to the horizontal. In addition, in this embodiment pivot rod 82 is generally parallel to inclined upper edge 64 of end plate 14.

A platen 34 for receiving a die part is provided, see FIGS. 2, 4, and 12. Brackets 86 are secured to the rear of plate 8 and each bracket includes an outwardly proecting ear member 88. The ear members 88 are in spaced relation to each other and are provided with aligned pivot rod receiving openings through which pivot rod 82 extends. With this arrangement, platen 84 is pivotally mounted on pivot rod 82, see FIG. 5, and, as described below, is tiltable between a vertical position as shown in FIGS. 1 and 2 and the opened-up position shown in FIGS.

l riage plate 30 is inclined at an angle of about 45 degrees to the horizontal. Two bracket members 94 and 96 are mounted on carriage plate 311. These bracket members are generally L-shaped with bracket member 94 having a mounting flange 9'8 and a support plate 100, while bracket member 96 has a mounting flange 102 and a support plate 1M. The mounting flanges 98 and 102 are secured to surface 1% of carriage plate 30. Support plates 1% and 104- are positioned so they extend longitudinally of the press in a generally perpendicular direction from the inclined upper edge 92 of carriage plate 30.

Support plates 1% and we are provided with aligned openings in which a pivot rod 1G8 is mounted. With this arrangement, pivot rod 108 is inclined to the horizontal, and in this embodiment is parallel to upper edge 92 of carriage 30 and to pivot rod 82.

A platen 11d (FIGS. 1 and 2) for receiving a die part is provided. Brackets 111 (P16. 2) are secured to the rear of platen 110, and each bracket includes an outwardly projecting ear member 112. These ear members are in spaced relation to each other and are provided with aligned openings through which pivot rod 1113 extends. With this arrangement platen is pivotally mounted on pivot rod 168, and, as will be described below, is tiltable between a vertical position as shown in FIG. 2, and the opened-up position shown in H6. 3. To insure free pivotal movement of the platen 11th when a heavy die part is secured thereto, thrust bearings 113 (FIGS. 1 and 2) are mounted on pivot rod 168 between ear members 112 and support plates 11519 and 164.

Male and female die parts 114 and 11s are shown respectively mounted on plates 84 and 11% in FIGS. 1 and 2. Such die parts must have substantially perfect mating surfaces 115 and 117 (FIGS. 2 and 3) in order to function properly.

The die spotting process requires that the die supporting surfaces of platens 84, and 11% be exactly parallel to each other when the die parts are moved together. Thus, the platens must be locked in vertical planes, as shown in FIG. 2, before the surfaces 115 and 117 of the male and female die parts 114 and 116 mounted on these platens are brought together in mating engagement.

To permit inspection and the laborious and painstaking machining operations, the die parts are pivotable into a generally common plane inclined to the horizontal as shown in FIG. 3 where the die parts incline upwardly from the front to the rear of the press at convenient height above the floor. With this arrangement, regardless of the size of the die parts a workman is able to inspect the die parts from the front of the machine, and he Will not have to climb on or between them.

Since the die parts usually are large and heavy, a suitably powered mechanism for pivoting the platens is provided.

The illustrated mechanism for pivoting platen 84 includes a hydraulic cylinder 11$ pivotally mounted on end plate 14, see FIGS. 1, 7, 12 and 13. As best seen in FIG. 12, cylinder 113 extends through an opening 12%) formed in end plate 14. An end cap 122 with oppositely extending trunnions 124 secured thereto is attached to the inner end of cylinder 118. These trunnions are rotatably mounted in spaced bearings 126 secured to inner surface 80 of end plate 14. A piston rod 123, secured at one end to a piston (not shown) in cylinder 11%, has its other end pivotally connected to free end 35 of platen 34-, see F168. 7 and 13.

Cylinder 118 is provided with suitable electrically operated valves (not shown) at each end of the piston.

To avoid misalignment damage to the die parts being worked on, it is necessary that the platens be locked in vertical position before they are moved together. The mechanism for so locking platen 84, as shown, includes a keeper-latch assembly. As best seen in FIG. 12, a rod 13d is rotatably journalled in aligned openings in the ends of support plates '74 and 78. A latch member 132 inacre 770 eluding a cam 133 is rigidly mounted on rod 131) near one end, and a latch member 134 is rigidly mounted on rod 136 near the other end, see FIGS. 9, and 12.

In addition, a biasing mechanism is provided to urge latch members 132 and 134 toward the inner surface 80 of end plate 14. As best seen in FIGS. 6 and 13, this biasing mechanism includes an arm 136 rigidly secured to rod 130. A spring shaft 138 is pivotally secured to the free end of arm 136. The opposite end of spring shaft 138 is slidably received by bracket 140 which is mounted on support plate 78. A spring 142 surrounds spring shaft 138 and is confined between bracket 14% and collar 144 on shaft 138. With this arrangement, spring shaft 138 is urged against the free end of arm 136, causing the desired biasing'torque to be exerted on rod 13b The free end 85 of platen 84 has keeper members 146 on each side thereof, see FIGS. 14, and 16. These keeper members are engaged by latch members 132 and 134 when platen 84 is exactly vertical, see FIG. 16. This positively locks platen 84 in vertical position. In addition, in this vertical position, an actuating plunger 141 (FIG. 6) of control switch 139 is engaged by a member 143 suspended below platen 84. This engagement actuates control switch 139, as will be seen.

To disengage latch members 132 and 134 from keeper members 14-6, a forked bracket 148 (FIGS. 7, 12, 13 and 17) is provided on the free end of piston rod 128. A cam roller 150 is rotatably mounted between the tines of bracket 148. As seen in FIGS. 7 and 13, cam roller 1517 is offset from the axis of the piston rod 128. In addition, as seen in FIGS. 7 and 17, bracket 148 is provided with oppositely and outwardly extending pins 152 which function as described below.

The free end 85 of platen 84 is provided with spaced brackets 154, see FIGS. 7 and 15. Downwardly inclined and parallel guide pin recesses 156 are formed in the facing surfaces of brackets 154, and the ends of pins 152 ride in these guide pin recesses.

As stated above, cylinder 118 is pivotally mounted on end plate 14, see FIG. 7. Consequently when the hydraulic ssytem (not shown) connected to cylinder 118 is actuated so piston rod 128 moves out of the cylinder 118, the engagement between pins 152 and recesses 156 first causes the cylinder 118 to pivot on trunnions 124 in clockwise direction (FIG. 7). With this movement cam roller 15!) engages cam 133 of latch member 132 and rotates the latter in clockwise direction. Thus latch member 132 is disengaged from associated keeper member 146, as seen in dotted lines in FIG. 16. At the same time, rod 131 and other latch member 134 rotate to disengage the latter from its associated keeper member 146.

This unlatching movement frees platen 84 from locked vertical position. Continued outward movement of piston rod 128 causes platen 84 to pivot on pivot rod 82. This pivoting movement continues (unless stopped) until piston rod 128 is completely extended, and this is designed to occur when platen 84 reaches the position shown in PEG. 3. Platen 84 may be maintained in this position by hydraulic pressure exerted on the piston rod128, although other means for doing this are possible.

When the hydraulic control system is actuated so that piston rod 128 moves back into cylinder 118, the reverse occurs. As piston rod 128 tilts platen 84, cam surfaces 147 (FIGS. 13, 14 and 16) on keeper members 146 strike latch members 132 and 134, moving the latter to establish latching engagement with the aid of biasing spring 138. When this occurs, platen 84 again is locked in vertical position.

The mechanism used for pivoting platen 111i is generally the same as that used for pivoting platen 84. As seen in FIGS. 3 and 18, it includes a hydraulic cylinder 161i pivotally mounted on movable carriage plate 30. As best seen in FIG. 8, cylinder 160 extends through an opening 162 in carriage plate 30. An end cap 164 with .6 oppositely extending trunnions 166 secured thereto is mounted on the inner end of cylinder 16% These trunnions 166 are rotatably journalled in spaced bearings 168 mounted on surface 1116 of carriage plate 31 A piston rod 170, secured at one end to a piston (not shown) in cylinder 161?, has its other end pivotally connected to the free end of platen 1111.

Cylinder is provided with suitable valves (not shown) at each end of the piston.

As seen in FIGS. 8 and 18, a rod 172 is rotatably journalled in aligned openings in previously mentioned support plates 100 and 1114. A latch member 174 including cam 175 like that on platen 84 and shown in FIG. 9 is rigidly mounted on rod 172 near one end thereof. In addition, a latch member 1'76 like that shown in FIG. 10 is rigidly mounted near the other end of rod 172.

A biasing mechanism for pivoting the latch members 174 and 176 is provided. This biasing mechanism, like that described in connection with platen 84, includes an arm 178 rigidly secured on rod 172, see FIG. 8. A spring shaft 188, see FIG. 18, is pivotally secured at one end to the free end of arm 178, and its opposite end is slidably received in bracket 182 which is mounted on support plate 104. A spring 184 surrounds spring shaft 188 and is confined betwen bracket 182 and collar 186 on shaft 180. With this arrangement, the spring shaft is urged against the free end or" arm 17 8, causing the desired torque to be exerted on rod 172.

The free end of platen 110 is provided with keeper members 188, see FIG. 18, shaped and positioned like those shown in FIGS. l4, l5 and 16 on platen 84. These keeper members are designed to be engaged by latch members 174 and 176 when the platen is exactly vertical, at which time platen 110 is locked. in its vertical position. In addition, a control switch like switch 139 shown in FIG. 6 is actuated when platen 111i is properly locked.

To disengage the latch members 174 and 176 from keeper members 188 and permit platen 116 to be pivoted to the position shown in FIG. 3, spaced brackets 198 (FIG. 18) are secured to the free end of platen 118. Downwardly inclined and parallel guide pin recesses 192 are formed in the facing surfaces of these brackets. The free end of piston rod 170 is exactly like the free end of piston rod 128, and pins 194 thereof ride in the guide pin recesses 192.

The above described parts operate the same way as described in connection with platen 84, so that when the hydraulic control system is operated to cause piston rod 170 to move out of cylinder 166, the cylinder 16!) is first pivoted downwardly to free the locking engagement between latch members 174 and 176 and keeper members 188. Continued outward movement of piston rod 170 pivots platen 110 to the position shown in FIG. 3, or some intermediate position at which the movement may be stopped.

As previously stated, carriage plate 30 is connected to the free end of piston rod 44 so that the carriage plate can be moved back and forth along guide bars 22, 24 and 26. To avoid deformation in carriage plate 31 caused by concentration of force by piston rod 44, a piston rod extension 195 (FIG. 18) may be secured to the side of carriage plate 30 opposite to that of piston rod 44. Free, end 1% of this piston rod extension is provided with a bearing block 198. This bearing block is designed to bear against platen 111] when the platen is in its vertical position. With this arrangement, the force applied by piston rod 44 to carriage plate 30 as the carriage plate is moved along the guide rods is distributed between the carriage plate and the platen 111 Die parts 114 and 116 are secured to platens 84 and 110 by any conventional means, and positioning members 208, best seen in FIG. 4, are mounted on the platens to help retain the dies in desired position.

The performance of the die spotting process requires the die parts to first be moved together as shown in FIG.

1, then separated as shown in FIG. 2, and finally, in the illustrated machine, pivoted to the inclined position shown in PEG. 3, where die parts of any size can be finished without the workman climbing on or between the die parts.

These dies are expensive, and it is apparent that suitable automatic controls are desirable for stopping carriage 30 when die parts 114 and 1145 are brought to gether. This must be done before the force of engagement of the die parts is sufiicient to cause damage. In addition, it is necessary to separate the die parts far enough so their free ends will avoid interference when they are pivoted into the position shown in FIG. 3. It also is desirable to stop carriage plate 30 automatically when the die parts are sufiiciently separated. To provide these automatic features, limit switches are used with the electrically operated cylinder valves.

As seen in FIG. 1, an overhead support 2&2 extending the length of the press is mounted on brackets 204 and 205 secured to end plates 14 and 16. Adjustably positioned cam members 2% and 2119 are carried by support 202. A control switch 212 is mounted on the bearing 32 associated with guide bar 24. This control switch has an operating lever 21 4. Cam members 268 and 210 are held positively in the path of operating lever 214 by means of aligning trolley 211 extending between bearing 32 and support 202. With this arrangement, when carriage plate 30 is moved one direction or the other, operating lever 214 eventually engages and is deflected by either of cam members 2&8 and 216 to actuate control switch 212.

An additional control switch 216 (FIG. 1) is mounted on the end of cylinder 42. This control switch has an actuating arm 218 which is adapted to be engaged by a push member 220 secured to carriage plate 30 so that when the dies are separated a predetermined amount, push member 220 actuates switch 216.

The controls for the die spotting press include a main switch 222 (FIG. 1) for operating the hydraulic pump and conventional control system (not shown). A control element 224 is associated with and operatively connected to cylinder 42. Control element 224 has three positions. One is the neutral position and the other two are operating positions. 'In one operating position the valves of cylinder 42 are actuated so piston rod 44 moves out of the cylinder and causes the die parts 114 and 116 to move together. In the other operating position piston rod 44 moves back into cylinder 42 causing carriage plate 30 and die part 116 to move away from die part 114.

Switch 212 on hearing 32 is connected to the control circuit in such a way that when it is actuated it slows down the travel speed of piston rod 44 in either direction. Actuation of switch 212 occurs just prior to the terminal positions of piston rod 44. Since die parts vary in thickness, the positions of cams 208 and 210 on support 202 must be adjusted for each pair of die parts so that the travel speed of carriage plate 3% will be reduced at the proper positions.

In addition, switches 139, see FIG. 6, associated with platens 84 and 110 are connected in circuit with the valves of cylinder 42 so that, unless switches 139 are actuated, control element 224 will be inoperative to cause movement of carriage plate 3% and die part 116. These switches, as seen in FIG. 6, are only actuated when platens 84 and 110 are vertical, and hence parallel to each other. This parallel relationship between the platens is important because unless the platens are parallel before they are moved together, the die spotting procedure cannot be performed successfully, and misaligned die parts are subject to damage when engaged. With the present arrangement, die parts 114 and 116 cannot be moved into engagement unless they are properly aligned.

Cylinder 118 on end plate 14 is controlled by threeposition control element 226. This element has a neutral center position, as shown in FIG. 1, and two angular L) operative positions. In one of these operative positions, the valves of cylinder 118 are actuated so piston rod 12% moves out of cylinder 118 and pivots platen 84 to the position shown in FIG. 3. When this happens, switch 139 is effective to render control element 224 inoperative to move carriage plate 30. When control element 226 is moved to its other operative position, piston rod 128 is moved back into cylinder 118, causing platen 84 to resume its vertical position. Action of switch 13% renders control element 224 again operative.

Similarly, control element 228 controls cylinder 160 and operates the same way as control element 226 to cause piston rod 179 to move out of and back into cylinder 160, and hence pivot platen from its vertical position to the FIG. 3 position, and vice versa.

It is apparent that there is a chance for the free ends of platens 84 or the die parts thereon to interfere with each other unless they are separated suiiiciently before they are pivoted. To make certain of this required separation, switch 216, see FIG. 1, is connected to control elements 226 and 228 and overrides them unless actuated. As seen in PEG. 3, actuation of switch 216 occurs when piston rod 44 is fully retracted.

Mating surfaces and 117 of die parts 114 and 116 must be brought together at just the right pressure in order to practice the die spotting process. This pressure is critical since too much pressure could damage the die parts, and too little pressure is unsatisfactory for the process. The required pressure adjustment is provided by moving cylinder 42 longitudinally. Rotation of control wheel 54 (FIGS. 1 and 18) moves cylinder 42 and carriage plate 29 toward or away from platen 84 with fine adjustment.

In operation, die parts 114 and 116 are suitably mounted on platens 84 and 116. One of the dies is coated with bluing or other material. Main switch 222 is actuated to start the hydraulic system. Next, control elements 226 and 228 are operated to pivot platens 84 and 119 and the die parts they carry into the vertical position shown in FIG. 2. Then control element 224 is operated to bring the die parts into mating engagement as shown in FIG. 1. After this, control elements 224, 226 and 225 are operated to restore the die parts to the inclined position shown in FIG. 3. In this position the uncoated die part easily can be inspected for transfer marks indicating high spots, and there is never any occasion to climb on or between the die parts. In addition, in this position it is easy to grind or file these high spots. Then the operation is continued until absence of transfer marks indicates that the mating surfaces are perfect, as is well known in the art.

Because of the convenience in working on the present die spotting press, dies of any size and shape can be inspected and machined by only one man, and from only the front side of the press.

While the press here illustrated and described has longitudinal movability of only one of the platens, namely platen 114), it will be understood that both platens may be longitudinally movable, if desired.

Also, the invention may be embodied in other forms without departing from the spirit or essential characteristics thereof as set forth in the claims, and the present embodiment is therefore to be considered as illustrative and not restrictive, and it is intended to include all changes which come within the scope and range of the claims. I

I claim:

1. A die spotting press comprising a frame including a pair of horizontally spaced vertical end plates connected together by at least one guide bar, a vertical carriage plate slidably mounted for longitudinal movement on said guide bar, a pair of die-supporting platens, one platen pivotaliy mounted on one end plate and the other platen pivotally mounted on said carriage plate, the pivotal axis of each platen inclined so the platens are movable between vertical positions facing each other and inclined positions sloping upwardly from the front to the rear of the press, a first hydraulic cylinder mounted on said frame, a first piston rod reciprocally movable in said cylinder and connected to said carriage plate to move the latter back and forth on said guide bar, a second hydraulic cylinder pivotally mounted on said one end plate, a second piston rod reciprocally movable in said second cylinder and connected to said one platen for pivoting same between vertical and inclined positions, a third hydraulic cylinder pivotally mounted on said carriage plate, a third piston rod reciprocally movable in said third cylinder and connected to said other platen for pivoting same between vertical and inclined positions whereby mating surfaces of dies mounted on said platens can be moved selectively into vertically positioned mating engagement and separated into inclined positions sloping upwardly from the front to the rear of the press, means locking said platens in vertical positions and for unlocking said platens when they are to be pivoted to inclined positions, a switch associated with each platen, each switch actuated only when the associated platen is in vertical position, means responsive to said switches to prevent movement of said carriage plate unless said platens are in vertical positions, and limit means effective to limit longitudinal movement of said carriage plate.

2. The die spotting press described in claim 1 including limit means mounted on said frame and operatively connected to said second and third cylinders to prevent said cylinders from pivoting said platens in the absence of predetermined spacing between said platens.

3. The die spotting press described in claim 1 including means regulating the pressure of engagement between the mating surfaces of die parts mounted on said platens.

4. The die spotting press described in claim 1 wherein said first cylinder is adjustably mounted on said frame for longitudinal movement whereby the pressure of engagement between the mating surfaces of the dies is regulated.

5. A die spotting press including a pair of support members horizontally spaced from each other and defining thereby a frame, at least one of said support members mounted for movement toward and away from the other support member, a die-holding member pivotally mounted on each support member, the pivotal axis of each dieholding member positioned so the mating surfaces of die parts held by said die-holding members are movable between positions where the mating surfaces of the die parts face each other for mating engagement and positions where the mating surfaces of the die parts are adjacent to and face outwardly from the front of said frame.

6. A die spotting press comprising a frame, said frame including a pair of horizontally spaced, vertical support plates, at least one of said vertical support plates mounted for horizontal movement toward and away from the other vertical support plate, a die-holding member pivotally mounted on each support plate, the pivotal axis of each die-holding member positioned so the mating surfaces of die parts held by said die-holding members are movable between positions where the mating surfaces of the die parts face each other for mating engagement and positions where the mating surfaces of the die parts are adjacent to and face outwardly from the front of said frame.

7. A die spotting presscomprising a frame, said frame including a pair of horizontally spaced, vertical support plates, at least one of said vertical support plates mounted for horizontal movement toward and away from the other vertical support plate, a die-supporting platen pivotally mounted on each support plate, the pivotal axis of each platen positioned so the die-engaging surfaces of the platens are movable between positions where they face each other to positions where they are adjacent to and face outwardly from the front of said frame, and means for moving at least one of said support plates toward the other and for pivoting the platens on the support plates whereby the mating surfaces of die parts mounted on said platens selectively can be moved into mating engagement with each other and moved so they are adjacent to and face outwardly from the front of said frame.

8. A die spotting press comprising a frame, said frame including a pair of horizontally spaced, vertical end plates connected together by at least one horizontal guide bar, a carriage plate slidably mounted for horizontal movement on said guide bar, a die-supporting platen pivotally mounted on one end plate and a die-supporting platen mounted on said carriage plate, the pivotal axis of each platen positioned so the die-engaging surfaces of the platens are movable between positions Where they face each other and positions where they are adjacent to and face outwardly from the front of said frame, and means moving the carriage plate on said guide bar and for pivoting the platens whereby the mating surfaces of die parts mounted on said platens selectively can be moved into mating engagement with each other and moved so they are adjacent to and face outwardly from the front of said frame.

9. A die spotting press comprising a frame having a pair of horizontally spaced, vertical end plates connected together by at least one horizontal guide bar, a carriage plate slidably mounted for horizontal movement on said guide bar, a die-supporting platen pivotally mounted on one end plate and a die-supporting platen mounted on said carriage plate, the pivotal axis of each platen parallel to said end plates and inclined so the die-engaging surfaces of the platens are movable between vertical positions where they face each other and inclined positions parallel to said guide bar and adjacent to and outwardly facing from the front of said frame, and means for moving said carriage plate on said guide bar and for pivoting the platens whereby the mating surfaces of die parts mounted on said platens selectively can be moved into vertical mating engagement with each other and moved so they are inclined, parallel to said guide bar and adjacent to and outwardly facing from the front of said frame.

10. The die spotting press described in claim 9 including means releasably and automatically locking said platens in vertical positions.

11. A die spotting press comprising a frame having a pair of horizontally spaced, vertical end plates connected together by at least one horizontal guide bar, a carriage plate slidably mounted for horizontal movement on said guide bar, die supporting platens pivotally mounted on one end plate and on said carriage plate, the pivotal axis of each platen parallel to said end plates and inclined so the die engaging surfaces of the platens are movable between vertical positions where they face each other and inclined positions parallel to said guide bar and adjacent to and outwardly facing from the front of said frame, a first means for reciprocally moving said carriage plate on said guide bar, second and third means for reciprocally pivoting the platens on said end plate and on said carriage plate, respectively, whereby the mating surfaces of die parts mounted on said platens selectively can be moved into vertical mating engagement with each other and moved so they are inclined and adjacent to and face outwardly from the front of said frame, means for releasably locking said platens in vertical positions, and control means associated with each platen for disabling said first means to prevent horizontal movement of said carriage plate unless said platens are in vertical position.

References Cited in the file of this patent UNITED STATES PATENTS 2,344,692 Fullerton Mar. ;21, 1944 2,807,969 Boyko Oct. 1, 1957 

